Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Driver Door Key Switch Signal | 1 | 1 | 1 | -- |
Driver Door Latch Low Reference | -- | 1 | -- | -- |
1. Key Cylinder Switch Inoperative | ||||
Circuit/System Description
The key cylinder unlock feature will unlock the driver door only with a single turn to the unlock position and all of the doors when the driver door switch (DDS) receives two consecutive turns to the unlock position and will send a request to the passenger door switch (PDS) and the BCM to unlock all of the doors.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, insert the key into the driver’s door lock cylinder and observe the scan tool Door Key Cyl. Unlock Switch parameter while turning the key to the UNLOCK position, the parameter should change between Idle and Unlock.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the driver door latch.
- Test for less than 1 ohm between the low reference circuit terminal 8 and ground.
- Ignition ON, verify the scan tool Door Key Cyl Unlock Switch parameter is Idle.
- Install a 3A fused jumper wire between the signal circuit terminal 9 and ground, verify the scan tool Door Key Cyl Unlock Switch parameter is Unlock.
- If all circuits tests normal, test or replace the driver door latch.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the DDM |
| ⇒ | If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuits test normal, replace the DDM. |
| ⇒ | If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the DDM. |
Component Testing
- Ignition OFF, disconnect the harness connector at the driver door latch.
- Test for infinite resistance between the signal terminal 9 and the low reference terminal 8 with the switch in the open position.
- Test for less than 2 ohms between the signal terminal 9 and the low reference terminal 8 with the switch in the Unlock position.
| ⇒ | If not the specified value, replace the driver door latch. |
| ⇒ | If greater than the specified range, replace the driver door latch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for DDM replacement, setup, and programming |
